Fabrication of Micro-channels on Polymethyl Methacrylate (PMMA) Plates by Thermal Softening Process Using Nichrome Wire: Tool Design and Surface Property Evaluation

The purpose of modelling the processes of compression and thermal softening of particulate, as well as porous and anisotropic materials is to determine the critical stress condition which initiates plastic flow of the material. This value is critical for the effectiveness of thermal softening process and depends on the thermo-mechanical parameters of the material and the key parameters of the process itself [2,4]. As it has been proven by research, the strength of materials such as wood and sawdust evidently decreases with the increase of temperature, influenced also by the moisture content of the material. For determining the distribution of temperature in a layer of thermally softened material it is indispensable to determine the heat transfer coefficient. This paper presents a test fixture for measuring heat conduction in natural composites materials, allowing for the effect of temperature, developed by the author.

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Process Planning and Tool Design of Magnetorehological Jet Finishing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.44-47.222 ◽

2010 ◽

Vol 44-47 ◽

pp. 222-226 ◽

Cited By ~ 3

Author(s):

Hao Bo Cheng ◽

Tan Wang ◽

Yun Peng Feng ◽

Yeung Yam

Keyword(s):

Process Optimization ◽

Process Planning ◽

Optical Materials ◽

Tool Design ◽

Uniform Thickness ◽

Promising Technique ◽

Optical Components ◽

Micro Channels ◽

Surface Patterns

Magnetorehological jet finishing (MJF) for optical materials is a promising technique, which characterized as polishing arbitrary surface patterns and correction plates, micro-channels, thin ultra-uniform thickness substrates and near perfect optical components. The process and the machine are complicated. This paper is concerned with the process optimization and tool design, and results obtained by FEA on the designed MJF tool.

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Rheological Behavior of Polymethyl Methacrylate (PMMA) Filling through Micro Channels

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.451 ◽

2011 ◽

Vol 189-193 ◽

pp. 451-454 ◽

Cited By ~ 1

Author(s):

Bin Xu ◽

Yu Bin Lu ◽

Guang Ming Li ◽

Song Xue ◽

Bei Ping Xiang

Keyword(s):

Polymethyl Methacrylate ◽

Rheological Behavior ◽

Capillary Flow ◽

Rapid Development ◽

Polymer Melt ◽

Characteristic Size ◽

Micro Channel ◽

Channel Characteristic ◽

Micro Channels ◽

The Difference

With the rapid development of micro injection molding, the determination of melt rheological behavior within micro mold cavity is very important for the accurate simulation modeling. Yet several investigations show the viscosity of melt decreases with the reduction of micro channel characteristic size, but there has been no sufficient experimental data for the conclusion. In this paper, depending on the capillary flow model, the measurement experiments of polymer melt viscosity were investigated when Polymethyl Methacrylate (PMMA) was extruded through the micro channel dies of 1000μm ,500μm and 350μm diameter. Test results show that, as micro-channel size decreases, the viscosity increases and the difference of viscosities in different micro channels reduces with increasing shear rate. This indicates microscopic scale melt rheological behavior of PMMA is different from that of other materials.

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NiAl precipitation in Fe-12w/o Cr-5w/o Ni-4w/o Al

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007480x ◽

1983 ◽

Vol 41 ◽

pp. 202-203

Author(s):

L.E. Murr ◽

J.S. Dunning ◽

S. Shankar

Keyword(s):

Solid Solution ◽

Stainless Steel ◽

Stainless Steels ◽

Alloy Composition ◽

Chromium Content ◽

Scale Up ◽

Optical Metallography ◽

Property Evaluation ◽

310 Stainless Steel ◽

Microstructural Studies

Aluminum additions to conventional 18Cr-8Ni austenitic stainless steel compositions impart excellent resistance to high sulfur environments. However, problems are typically encountered with aluminum additions above about 1% due to embrittlement caused by aluminum in solid solution and the precipitation of NiAl. Consequently, little use has been made of aluminum alloy additions to stainless steels for use in sulfur or H2S environments in the chemical industry, energy conversion or generation, and mineral processing, for example.A research program at the Albany Research Center has concentrated on the development of a wrought alloy composition with as low a chromium content as possible, with the idea of developing a low-chromium substitute for 310 stainless steel (25Cr-20Ni) which is often used in high-sulfur environments. On the basis of workability and microstructural studies involving optical metallography on 100g button ingots soaked at 700°C and air-cooled, a low-alloy composition Fe-12Cr-5Ni-4Al (in wt %) was selected for scale up and property evaluation.

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